Ptolemy's Greek name, Ptolemaeus (Πτολεμαῖος, Ptolemaîos), is an ancient Greek personal name. It occurs once in Greek mythology and is of Homeric form.[12] It was common among the Macedonian upper class at the time of Alexander the Great and there were several of this name among Alexander's army, one of whom made himself pharaoh in 323 BC: Ptolemy I Soter, the first pharaoh of the Ptolemaic Kingdom. Almost all subsequent pharaohs of Egypt, with a few exceptions, were named Ptolemies until Egypt became a Roman province in 30 BC, ending the Macedonian family's rule.[13][14]
The name Claudius is a Roman name, belonging to the gens Claudia; the peculiar multipart form of the whole name Claudius Ptolemaeus is a Roman custom, characteristic of Roman citizens. Several historians have made the deduction that this indicates that Ptolemy would have been a Roman citizen.[16] Gerald Toomer, the translator of Ptolemy's Almagest into English, suggests that citizenship was probably granted to one of Ptolemy's ancestors by either the emperor Claudius or the emperor Nero.[17]
The 9th century Persian astronomer Abu Ma'shar al-Balkhi mistakenly presents Ptolemy as a member of Ptolemaic Egypt's royal lineage, stating that the descendants of the Alexandrine general and Pharaoh Ptolemy I Soter were wise "and included Ptolemy the Wise, who composed the book of the Almagest". Abu Ma'shar recorded a belief that a different member of this royal line "composed the book on astrology and attributed it to Ptolemy". We can infer historical confusion on this point from Abu Ma'shar's subsequent remark: "It is sometimes said that the very learned man who wrote the book of astrology also wrote the book of the Almagest. The correct answer is not known."[18] Not much positive evidence is known on the subject of Ptolemy's ancestry, apart from what can be drawn from the details of his name, although modern scholars have concluded that Abu Ma'shar's account is erroneous.[19] It is no longer doubted that the astronomer who wrote the Almagest also wrote the Tetrabiblos as its astrological counterpart.[20] In later Arabic sources, he was often known as "the Upper Egyptian",[21] suggesting he may have had origins in southern Egypt.[22] Arabic astronomers, geographers and physicists referred to his name in Arabic as Baṭlumyus (Arabic: بَطْلُمْيوس).[23]
Ptolemy wrote in ancient Greek and can be shown to have utilized Babylonian astronomical data.[24][25] He might have been a Roman citizen, but was ethnically either a Greek[2][26][27] or at least a Hellenized Egyptian.[26][28][29]